Photonic crystal nanofluid sensor

Abstract

The utility model relates to a photonic crystal nanofluid sensor which comprises a glass substrate, a grating layer arranged on the top of the glass substrate, a material layer arranged on the top of the grating layer, an optical transparent covering layer arranged on the top of the material layer, a plurality of grating grooves arranged on the top of the grating layer, and shape memory alloy sheets fixed on two sides inside the plurality of grating grooves. According to the utility model, the advantages of the photoresponse liquid crystal elastomer (LCE) and the magnetic photonic crystal are combined, the dual functions of illumination triggering and magnetic field guiding are realized, and through the contraction and restoration of the LCE, the light-operated mechanical switch can be used as a light-operated mechanical switch to realize non-contact flow channel control; the method has obvious advantages in the aspects of automation and remote control.

Description

Technical Field

[0001] This utility model relates to the field of optoelectronic devices, specifically a photonic crystal nanofluid sensor. Background Technology

[0002] Photonic crystal nanofluidic sensors possess the relevant properties of photonic crystals, namely, the ability to resonate with wavelengths of specific frequencies and to enhance the local electric field within the nanochannel. Therefore, photonic crystal nanofluidic sensors can be applied to label-free detection based on resonant wavelength shifts and fluorescence-enhanced detection based on local electric field enhancement. The nanofluidic structure, with its small volume and large surface area ratio, facilitates the rapid detection of analytes on the inner surface of the nanochannel within the grating. The relevant properties of nanofluids make them suitable for detecting low-concentration small molecules, proteins, genes, and DNA, offering high detection accuracy and low processing time. Furthermore, the small volume of the nanofluidic channel is a core component for realizing on-chip systems. Currently, many research institutions have applied for patents related to photonic crystal and nanofluidic sensor research. For example, Professor Cunningham in the United States has used photonic crystals as sensors for a series of biochemical molecular detections; Brueck et al. have used nanofluidic sensors for biochemical analysis experiments and applied them to the separation and analysis of biomolecules.

[0003] According to publicly available patent 201621300674.4, a photonic crystal nanofluidic sensor, the sensor includes a photonic crystal structure and an optically transparent capping layer. The photonic crystal structure includes a glass substrate, a grating layer disposed on the glass substrate, and a material layer deposited on the grating layer. The grating layer has a grating periodic structure. The optically transparent capping layer is disposed on the upper surface of the material layer, forming a nanofluidic channel with the grating grooves of the grating layer. This photonic crystal nanofluidic sensor has advantages such as simple structure, strong applicability, high precision, and low cost, and can be mass-produced.

[0004] However, in practice, traditional photonic crystal nanofluid sensors primarily rely on the photonic crystal structure for detection of resonant wavelength shifts and localized electric field enhancements, resulting in relatively limited functionality. Furthermore, while they can utilize transmission spectroscopy for analysis and detection, reducing detection difficulty and improving stability, they still depend on specific optical platforms for testing. Moreover, the sensors are structurally fixed and lack the ability to dynamically adjust according to environmental conditions or detection requirements. Therefore, new technical solutions are needed to address these issues. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology, adapt to practical needs, and provide a photonic crystal nanofluid sensor. This addresses the problem that current traditional photonic crystal nanofluid sensors mainly rely on the photonic crystal structure for detection of resonant wavelength shift and local electric field enhancement, resulting in relatively limited functionality. Furthermore, although they can utilize transmission spectroscopy for analysis and detection, reducing detection difficulty and improving detection stability, they still rely on specific optical platforms for testing. Moreover, the sensors are structurally fixed and lack the ability to dynamically adjust according to environmental conditions or detection requirements.

[0006] To achieve the purpose of this utility model, the technical solution adopted by this utility model is as follows: a photonic crystal nanofluid sensor is designed, including a glass substrate, a grating layer on the top of the glass substrate, a material layer on the top of the grating layer, an optically transparent cover layer on the top of the material layer, a plurality of grating grooves on the top of the grating layer, shape memory alloy sheets fixed on both sides inside the plurality of grating grooves, and a flexible photonic crystal film on the surface of the shape memory alloy sheets.

[0007] Preferably, an inlet and an outlet are respectively provided on both sides of the bottom of the glass substrate, and an LCE thin film microvalve is provided on the inner wall of both the inlet and the outlet.

[0008] Preferably, a magnetic photonic crystal layer is integrated on the surface of the LCE thin-film microvalve.

[0009] Preferably, a permanent magnet array is pre-placed on the other side of the LCE thin-film microvalve.

[0010] Preferably, the inlet and outlet are respectively connected to multiple grating grooves, and the LCE thin film microvalve in the inlet and outlet is located at the intersection of the inlet and outlet and the grating groove.

[0011] Preferably, the material layer is cadmium sulfide, aluminum nitride, tantalum pentoxide, indium oxide, or borate glass, and its deposition thickness is 75-150 nm.

[0012] Preferably, the optically transparent coating layer is a polyester film, polydimethylsiloxane, polycarbonate, or epoxy resin.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0014] 1. This invention combines the advantages of photoresponsive liquid crystal elastomer (LCE) and magnetic photonic crystal, realizing the dual functions of light-triggered and magnetic field-guided operation. Through the contraction and recovery of LCE, it can be used as a photo-controlled mechanical switch to achieve contactless flow channel control, which has significant advantages in automation and remote control.

[0015] 2. This invention utilizes a magnetic field to guide the enrichment of magnetic target molecules and enhances the optical signal through a photonic crystal, thereby significantly improving the detection sensitivity. This active enrichment mechanism reduces the detection limit by two orders of magnitude, which is of great significance for trace analysis.

[0016] 3. This invention introduces a shape memory alloy sheet, which can automatically adjust the lattice spacing according to the pressure state, thereby enhancing the refractive index sensitivity and avoiding structural fatigue. This intelligent adaptability enables the sensor to maintain high performance under different conditions. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is a schematic diagram of the grating groove structure of this utility model;

[0019] Figure 3 This is a schematic diagram of the bottom structure of this utility model.

[0020] In the figure: 1. Glass substrate; 101. Grating layer; 102. Material layer; 103. Optically transparent cover layer; 104. Inlet; 105. Outlet; 2. Grating groove; 201. Shape memory alloy sheet; 202. Flexible photonic crystal thin film; 3. LCE thin film microvalve; 301. Magnetic photonic crystal layer; 302. Permanent magnet array. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0022] Example 1: A photonic crystal nanofluidic sensor, see [link to example]. Figures 1 to 3 The sensor comprises a glass substrate 1, a grating layer 101 on top of the glass substrate 1, a material layer 102 on top of the grating layer 101, an optically transparent capping layer 103 on top of the material layer 102, and multiple grating grooves 2 on top of the grating layer 101. Shape memory alloy sheets 201 are fixed to both sides of the interior of each of the multiple grating grooves 2. A flexible photonic crystal film 202 is deposited on the surface of the shape memory alloy sheet 201. When a sample to be tested is injected into the nanofluidic channel, the photonic crystal structure resonates with a specific frequency wavelength, enhancing the local electric field within the nanochannel. This enhancement effect can be used for label-free detection and fluorescence-enhanced detection. Because the shape memory alloy sheet 201 is fixed to both sides of the interior of the grating grooves 2, when fluid passes through the nanofluidic channel, it exerts pressure on the shape memory alloy sheet 201. Depending on the magnitude and state of the pressure, the shape memory alloy sheet 201 undergoes corresponding deformation, thereby adjusting the lattice spacing of the grating. This intelligent adaptability allows the sensor to dynamically adjust according to environmental conditions or detection requirements, enhancing refractive index sensitivity and avoiding structural fatigue.

[0023] For details, see Figure 3 An inlet 104 and an outlet 105 are respectively opened on both sides of the bottom of the glass substrate 1. LCE thin-film microvalves 3 are provided on the inner walls of both inlet 104 and outlet 105. The LCE thin-film microvalves 3 are located at the flow channel intersection nodes, and a magnetic photonic crystal layer 301 is integrated on their surface. Under 450nm illumination, the LCE undergoes significant shrinkage, with a shrinkage rate exceeding 40%. This shape change can precisely control the opening and closing of the nanofluidic channel, thereby achieving precise manipulation of the sample to be tested. The magnetic photonic crystal is composed of periodically arranged Fe3O4@SiO2 magnetic nanoparticles and has magnetic response characteristics. When an external magnetic field is applied, the magnetic photonic crystal layer 301 guides magnetic target molecules to accumulate in the nanofluidic channel, thereby improving detection sensitivity. Simultaneously, the synergistic effect of the magnetic photonic crystal layer 301 and the LCE thin-film microvalves 3 can further precisely control the accumulation location and degree of magnetic target molecules.

[0024] Further, see Figure 3 , , LCE thin film microvalve 3 surface integrated with magnetic photonic crystal layer 301.

[0025] It is worth noting that, see Figure 3 On the other side of the LCE thin film microvalve 3, a permanent magnet array 302 is pre-placed.

[0026] It is worth noting that, see Figure 1 and Figure 3 The inlet 104 and outlet 105 are respectively connected to multiple grating grooves 2, and the LCE thin film microvalve 3 in the inlet 104 and outlet 105 is located at the intersection of the inlet 104 and outlet 105 and the grating groove 2.

[0027] It is worth mentioning that, see Figure 1 The material layer 102 is made of cadmium sulfide, aluminum nitride, tantalum pentoxide, indium oxide, or borate glass, and its deposition thickness is 75-150 nm.

[0028] It is worth emphasizing that, see Figure 1 The optically transparent cover layer 103 is a polyester film, polydimethylsiloxane, polycarbonate or epoxy resin.

[0029] In a photonic crystal nanofluidic sensor, when a sample is injected into the nanofluidic channel, the photonic crystal structure resonates with a specific frequency wavelength, enhancing the local electric field within the nanochannel. This enhancement effect can be used for label-free detection and fluorescence-enhanced detection. Since the shape memory alloy sheet 201 is fixed on both sides of the grating groove 2, the fluid passing through the nanofluidic channel exerts pressure on the shape memory alloy sheet 201. Depending on the magnitude and state of the pressure, the shape memory alloy sheet 201 deforms accordingly, thereby adjusting the lattice spacing of the grating. This intelligent adaptability allows the sensor to dynamically adjust according to environmental conditions or detection requirements, enhancing refractive index sensitivity and avoiding structural fatigue. The LCE thin-film microvalve 3 is positioned at the flow channel intersection node, and its surface integrates a magnetic photonic crystal layer 301. Under 450nm illumination, the LCE undergoes significant shrinkage, with a shrinkage rate exceeding 40%. This shape change allows for precise control of the opening and closing of the nanofluidic channels, enabling precise manipulation of the sample. The magnetic photonic crystal, composed of periodically arranged Fe3O4@SiO2 magnetic nanoparticles, exhibits magnetic response characteristics. When an external magnetic field is applied, the magnetic photonic crystal layer 301 guides magnetic target molecules to accumulate within the nanofluidic channels, thereby improving detection sensitivity. Simultaneously, the synergistic effect of the magnetic photonic crystal layer 301 and the LCE thin-film microvalve 3 further allows for precise control of the accumulation location and degree of magnetic target molecules.

[0030] In summary, the photonic crystal nanofluid sensor, liquid crystal elastomer microvalve array, magnetic photonic crystal, and shape memory alloy sheet 201 together constitute a synergistic working mechanism. When light triggers the contraction of the LCE microvalve, the fluid flow path changes; simultaneously, the magnetic photonic crystal alters its optical properties under the influence of a magnetic field, further affecting the sensor's detection performance. Meanwhile, the shape memory alloy sheet 201 automatically adjusts the lattice spacing of the grating according to the fluid pressure state, maintaining the sensor's high performance. This multi-layered combination results in a sensor with higher detection accuracy, greater adaptability, and a wider range of applications.

[0031] In addition, all components designed in this utility model are general standard parts or components known to those skilled in the art. Their structure and principle can be learned by those skilled in the art through technical manuals or conventional experimental methods. Those skilled in the art can fully implement them, so there is no need to elaborate. The content protected by this utility model does not involve improvements to the internal structure and method.

[0032] The embodiments disclosed herein are preferred embodiments, but are not limited thereto. Those skilled in the art can readily grasp the spirit of this utility model based on the above embodiments and make different extensions and variations. However, as long as they do not depart from the spirit of this utility model, they are all within the protection scope of this utility model.

Claims

1. A photonic crystal nanofluidic sensor, comprising a glass substrate (1), characterized in that, The glass substrate (1) has a grating layer (101) on top, a material layer (102) on top of the grating layer (101), an optically transparent cover layer (103) on top of the material layer (102), a plurality of grating grooves (2) on top of the grating layer (101), and shape memory alloy sheets (201) fixed on both sides inside the plurality of grating grooves (2). A flexible photonic crystal film (202) is provided on the surface of the shape memory alloy sheet (201).

2. The photonic crystal nanofluidic sensor as described in claim 1, characterized in that, The glass substrate (1) has an inlet (104) and an outlet (105) on both sides of its bottom, and the inner walls of the inlet (104) and outlet (105) are provided with LCE film micro valves (3).

3. The photonic crystal nanofluidic sensor as described in claim 2, characterized in that, The LCE thin film microvalve (3) has an integrated magnetic photonic crystal layer (301) on its surface.

4. The photonic crystal nanofluidic sensor as described in claim 2, characterized in that, The LCE thin film microvalve (3) has a pre-placed permanent magnet array (302) on the other side.

5. The photonic crystal nanofluidic sensor as described in claim 2, characterized in that, The inlet (104) and outlet (105) are respectively connected to multiple grating grooves (2), and the LCE thin film micro valves (3) in the inlet (104) and outlet (105) are located at the intersection of the inlet (104) and outlet (105) and the grating groove (2).

6. The photonic crystal nanofluidic sensor as described in claim 1, characterized in that, The material layer (102) is cadmium sulfide, aluminum nitride, tantalum pentoxide, indium oxide, or borate glass, and its deposition thickness is 75-150 nm.

7. The photonic crystal nanofluidic sensor as described in claim 1, characterized in that, The optically transparent cover layer (103) is a polyester film, polydimethylsiloxane, polycarbonate or epoxy resin.

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